curbtender

Built a 60 cm Allez Epic for a friend who didn't ride road too much. I was surprised at seeing him ride it as a cross bike. More surprising was that it was holding together. Owned Alan, Specialized and, presently, a Miyata Titanium. None of them have separated but it is always in the back of my mind...thanks to these threads. I'm a 250 pounder so I'm sure I'm pressing the frame limits.

chain_whipped

Couldn't say if they're selling but recent ebay listings of various vintage carbon tubed bonded ally lugged bikes and frames seem to have a comeback and stronger prices vs a decade ago.

Less around, a renewed interest for collectors?

Brad L 

Here’s my 1989 Vitus 979 (all Mavic). These were introduced in 1979 and raced extensively in the 1980s by Sean Kelly, including at Paris Roubaix. They’re no slouch.

Arrowana

I've come across hundreds of bonded Treks, never found one that was separating. Seen dozens of Raleigh Techniums, two or three had lugs starting to separate. Only seen a few Vitus 979s, one had a cracked lug. Given enough time, I'd expect that even the bonded Treks will start to fail, but we aren't there yet.

plumberroy

I had a bonded frame mountain bike a few years ago. I don't remember what brand it was but it was one of the decent Japanese made ones I am a big guy and I had no concerns about it structurely it was just as stiff/ harsh riding as any other aluminum frame bike I have rode. I wanted to like it,but aluminum bikes just don't feel right to me

macstuff 

true it seems. There have been a few around here that get a lot of attention and sell quick.
The Treks that come in the coop get turned around and sell fast. All within 2 weeks. We're getting $350+/-
There is also a sweet centurian on the marketplace right now for 5 bills. It's a looker....

macstuff 

That's the video I mentioned.
I'm pretty sure the failure was due to the heat applied to the frame during the paint job. No matter which glue is used, aerospace quality or not, heat will cause it to fail.
Not talking ambient, but excessive or extended.
No matter what, it's prudent to think about these things.

Trakhak

People occasionally say they see evidence of Technium tubes separating from the lugs. In the examples I've seen, when they've posted pictures, it has always turned out that all that had happened was that the cosmetic rings Raleigh used to conceal the lug-to-tube seam had come loose, with the lug/tube bond still intact.

Chuckk

Got this 1984 Vitus from the original owner:


But it's badged as a Fraysse (Paris Sport) the importer


These empty roads aren't around Austin any more...

dddd

The Epic and (similarly Giant-built) Cadex frames had no metal core tube, but the Epic lugs did actually bond to both the inside and the outside of the carbon tubes, allowing shorter lug sockets.

And while the Epic (as tested on Bicycling's Tarantula apparatus) was one of the stiffer frames that they had tested, the Centurion Carbon was the flexiest!

My own Ironman Carbon had it's aluminum fork replaced with a Look carbon fork by it's previous owner, I don't feel any excess flex out of it since I weigh only 145lb at the moment, but it does soften the ride on chip seal while using 23mm tires.
Sadly, I did pass the lovely Helium wheels on to a new owner, but I did recoup almost the entire cost of the bike with that move, so...

bikamper

I have an early Technium 440 I picked up at ReStore for $70.

It still had the original tires on it and a sofa for a saddle. I hate stem shifters, so I went with bar-ends. I also just wrapped over the foam crap on the bars because it wasn't coming off without a fight. Anyway, it rides similar to my Miyata 710 and 600GT and I've seen no indication of separation at the lugs.

I did have a Miyata CarbonTech 3000. I got the frame for a song because it was built without shift lugs or cable guides. A friend who did CF layups patched it up where the holes were. I built a 18 lb fixed gear and rode the piss out of it. A guy came by with an open wallet and went home with it.

scozim 

Here's mine - absolutely love the ride of this bike. But, I admit I don't ride it as aggressively as I do my steel rides.

Deal4Fuji

SR Sakea Litage - AL into AL '89 I think

embankmentlb

Intersting video and test ride of a bonded frame. Bikeit uk

macstuff 

This vid is mentioned in the thread and linked already.

Chuckk

Seems to me that the advantage of bonded frames is simplification of assembly.
It let Trek continue manufacture in the USA until 1998 I think.
And they worked well! The 1xxx series wasn't light, but it rode like a steel bike.
The 2xxx series make great distance bikes.


1996 Trek 2100


1998 Trek 2300

Arrowana

Good to know, will take a closer look next time I see one that looks suspicious.

Chuckk

Yes! BOTH the 753 Techniums I've had showed paint failure and oxidation around the rings.
Not a good thing, but didn't seem to effect the joint.
The rings are ugly enough anyway.

dddd

That's the galvanic reaction of the small-surface-area steel ring being electrically overcome by the much greater surface area of the aluminum lug.
Keeping the frame clean and dry is the only way to prevent it, since even galvanizing the steel ring would not prevent it's surface from oxidizing (what galvanizing is supposed to do, act like a "sacrificial anode").

BMC_Kid 

No, they sure are not. The growth outside Austin has been insane. How old is that photo? I live in San Antonio and thankfully just a 30 minute ride from my house I am on roads that still look like your photo. I stopped meeting friends up in your neck of the woods and now they drive down my way and meet me closer to SA’s northwestern country when I am in town.

blamester

I will add I had a bonded seatpost fail. Not particularly dangerous at the time but it could have been. It failed slow. Thompson masterpiece I think.

dddd

Every Thompson post that I've seen was of one-piece construction, no welds, bonds or press fits.

Even their titanium post is I believe of one piece.

I've seen a good number of bonded (two-piece) posts either crack at the joint or have the joint's bonding fail, or both.

Chuckk

I never cared for the first generation Technium frames, but appreciate the second generation frames with aluminum lugs and 531, 753, carbon and titanium tubes!
Kent was really trying to show what the process could do.


1993 Raleigh USA MT500 Front half of the frame is 7005 double butted aluminum with only two bonding points to a Tange Prestige steel rear triangle.


1993 Raleigh USA Technium RT600 Competition - 531 mains and fork. Please forgive ugly bars and stem


Too small! 1990's Raleigh USA Team Technium - 753 mains and SR Litage fork. Drove too far for what was supposed to be a 58cm frame to pass it up.


As purchased two weeks ago 1990's Raleigh USA Team Technium -753 mains and fork (fork brazed by Raleigh in England). It will clean up and be ride-able, but missing FD bracket,

curbtender

After dealing with all the stuck seatpost I can see where steel to an aluminum lug would be a good idea.

Jmpierce

Mine an 86 I think. Shimano Tri-color and 600. I'm 265 lbs while I rode it and it never came apart. Mostly wall art these days.